|32 OpenMP Traps For C++ Developers - Alexey Kolosov, Andrey Karpov, Evgeniy Ryzhkov|
Since multi-core systems are spreading fast, the problem of parallel programming becomes more and more urgent. However, even the majority of experienced developers are new to this sphere. The existing compilers and code analyzers allow finding some bugs, which appear during parallel code development. However, many errors are not diagnosed. The article contains description of a number of errors, which lead to incorrect behavior of parallel programs created with OpenMP.
Keywords: OpenMP; errors; parallel programming
|PDMI Computer Science Club - PDMI Computer Science Club|
Lecture on parallel programming. Roman Elizarov.
Keywords: parallel programming, computer science club
|Is the Moore's Law dead? - Dave Wilson (Int'l Marketing Director)|
Keynote delivered by Victor Mieres, VP - Asia/RoW for National Instruments, during the 5th IEEE EAST-WEST DESIGN & TEST INTERNATIONAL SYMPOSIUM in Yerevan, Armenia, September 7-10, 2007. Author: http://www.ewdtest.com/conf/
Keywords: graphical system design labview parallel programming multiprocessors
|Influence of Cooling Hole Geometry and Material Conductivity on the Thermal Response of Cooled Silicon Nitride Plate - Abdul-Aziz, Ali|
To complement the effectiveness of ceramic materials and the applicability to turbine engine applications, a parametric study using the finite element method was carried out. This study conducted thorough analyses of a thermal-barrier-coated silicon nitride (Si3N4) plate specimen with cooling channels, where its thermal conductivity was verified in an attempt to minimize the thermal stresses and reach an optimal rate of stress...
Keywords: PARALLEL PROGRAMMING; COMPUTATION; MESSAGES; STANDARDIZATION; PROTOCOL (COMPUTERS); ADDRESSING
|MPI Requirements Of The Network Layer - Rich Brueckner|
In this slidecast, Jeff Squyres from Cisco describes the proposed successor to the Linux verbs API that is designed to better serve the needs of MPI.Learn more: http://blogs.cisco.com/performance/a-fun-thing-happened-on-the-way-to-the-openframeworks-discussion-today/#more-134672 Watch the video presentation: http://wp.me/p3RLHQ-beT
Keywords: hpc; supercomputing; MPI; OpenFrameworks; RichReport; insideHPC; Open Fabrics; parallel programming
|MIT 6.189 Multicore Programming Primer, January (IAP) 2007 - MIT OpenCourseWare|
View the complete course: http://ocw.mit.edu/6-189IAP07 Instructors: Rodric Rabbah, Saman Amarasinghe * NOTE: Recitations 1-3 are not available. The course serves as an introductory course in parallel programming. It offers a series of lectures on parallel programming concepts as well as a group project providing hands-on experience with parallel programming. The students will have the unique opportunity to use the cutting-edge PLAYSTATION 3 development platform as they learn how to design and i...
Keywords: multicore architectures; parallel programming patterns; Sony PlayStation 3; competition
|Results of the Round Robin on opening-load measurement conducted by ASTM Task Group E24.04.04 on Crack Closure Measurement and Analysis - Phillips, Edward P|
An experimental Round Robin on the measurement of the opening load in fatigue crack growth tests was conducted on Crack Closure Measurement and Analysis. The Round Robin evaluated the current level of consistency of opening load measurements among laboratories and to identify causes for observed inconsistency. Eleven laboratories participated in the testing of compact and middle-crack specimens. Opening-load measurements were made for crack growth at two stress-intensity factor levels, three cra...
Keywords: PARALLEL PROGRAMMING; SIMD (COMPUTERS); COMPUTER SYSTEMS PERFORMANCE; COMPUTER SYSTEMS PROGRAMS; HARDWARE
|Unsteady Flowfield Around Tandem Cylinders as Prototype for Component Interaction in Airframe Noise - Khorrami, Meldi R.|
Synergistic application of experiments and numerical simulations is crucial to understanding the underlying physics of airframe noise sources. The current effort is aimed at characterizing the details of the flow interaction between two cylinders in a tandem configuration. This setup is viewed to be representative of several component-level flow interactions that occur when air flows over the main landing gear of large civil transports...
Keywords: COMPLEX SYSTEMS; SPECIFICATIONS; MANUALS; PARALLEL PROGRAMMING; DISTRIBUTED PARAMETER SYSTEMS; CLAIMING; RESOLUTION
|Adoption of Parallel Genetic Algorithms for the Solution of System of Equations - Shilpa S Babalad, Anand M Shivapuji|
Analysis and understanding of physical systems require modeling the system as set of simultaneous linear/non linear equations and generating solutions to satisfy the system of equations. Analytical approach towards solving the system of equations remains practical so long as considerable constraints are imposed on the modeled system to bring in significant simplicity so as to retain the system model within the scope of defined algorithms for solving system of equations...
Keywords: Evolution; Genetic algorithms; parallel programming; system of equations; ijorcs; ijorcs.org
|Seal Technology for Liquid Oxygen (LOX) Turbopumps - Shapiro, Wilbur|
Two types of advanced seals for liquid oxygen (LOX) turbopumps were investigated. One was a spiral-groove face seal whose function is to seal high-pressure LOX at the impeller end of the turbopump. The other was a floating-ring, Rayleigh-step, helium buffered seal used to prevent LOX ingress to the turbine side of the unit. For each seal type, two sizes were investigated (50 and 20 mm). A turbine-driven test rig was designed and manufactured, and a test program was completed on the 50 mm floatin...
Keywords: ALGORITHMS; CONCURRENT PROCESSING; MULTIPROCESSING (COMPUTERS); SYNCHRONISM; COMPUTER SYSTEMS PERFORMANCE; LOGARITHMS; PARALLEL PROGRAMMING
|Control Systems - NON|
Boeing Commercial Airplane Company's Flight Control Department engineers relied on Langley developed software package known as ORACLS to develop an advanced control synthesis package for both continuous and discrete control system. Package was used by Boeing for computerized analysis of new system designs. Resulting applications include a multiple input/output control system for the terrain-following navigation equipment of the Air Forces B-1 Bomber, and another for controlling in flight changes...
Keywords: PARALLEL PROCESSING (COMPUTERS); MULTIPROCESSING (COMPUTERS); ALGORITHMS; COMPUTATIONAL GRIDS; PARALLEL PROGRAMMING; SUPERCOMPUTERS; LOADS (FORCES); MANY BODY PROBLEM; MATRICES (MATHEMATICS)
|Solar Selective Coatings for High Temperature Applications - Jaworske, Donald A.|
Solar selective coatings are envisioned for use on minisatellites, for applications where solar energy is to be used to power heat engines or to provide thermal energy for remote regions in the interior of the spacecraft. These coatings are designed to have the combined properties of high solar absorptance and low infrared emittance. The coatings must be durable at elevated temperatures. For thermal bus applications, the temperature during operation is likely to be near 100 C...
Keywords: PARALLEL PROGRAMMING; CENTRAL PROCESSING UNITS; NASA PROGRAMS; APPLICATIONS PROGRAMS (COMPUTERS); CLIMATE MODELS; PERFORMANCE TESTS; MEMORY (COMPUTERS); COMPUTER SYSTEMS PROGRAMS
|Atomistic Simulations of Ti Additions to NiAl - Bozzolo, Guillermo|
The development of more efficient engines and power plants for future supersonic transports depends on the advancement of new high-temperature materials with temperature capabilities exceeding those of Ni-based superalloys. Having theoretical modelling techniques to aid in the design of these alloys would greatly facilitate this development. The present paper discusses a successful attempt to correlate theoretical predictions of alloy properties with experimental confirmation for ternary NiAl-Ti...
Keywords: UNSTRUCTURED GRIDS (MATHEMATICS); SUPERCOMPUTERS; BALANCING; DYNAMIC LOADS; PARALLEL PROGRAMMING; AERODYNAMIC DRAG; SIMULATION; COMPUTATIONAL GRIDS; COST EFFECTIVENESS; PHYSICAL FACTORS; REFINING
|NDE Methodologies for Composite Flywheels Certification - Baaklini, George Y.|
Manufacturing readiness of composite rotors and certification of flywheels depend in part on the maturity of nondestructive evaluation (NDE) technology for process optimization and quality assurance, respectively. Capabilities and limitations of x-ray-computed tomography and radiography, as well as advanced ultrasonics were established on NDE ring and rotor standards with EDM notches and drilled holes...
Keywords: FORTRAN; PARALLEL PROGRAMMING; SOFTWARE ENGINEERING; COMPUTER PROGRAMS; COMPUTATIONAL FLUID DYNAMICS; THREE DIMENSIONAL MODELS; COMPUTATIONAL GRIDS; NAVIER-STOKES EQUATION; BOUNDARY CONDITIONS
|An Acoustic Charge Transport Imager for High Definition Television Applications: Reliability Modeling and Parametric Yield Prediction of GaAs Multiple Quantum Well Avalanche Photodiodes - Hunt, W. D.|
Reliability modeling and parametric yield prediction of GaAs/AlGaAs multiple quantum well (MQW) avalanche photodiodes (APDs), which are of interest as an ultra-low noise image capture mechanism for high definition systems, have been investigated. First, the effect of various doping methods on the reliability of GaAs/AlGaAs multiple quantum well (MQW) avalanche photodiode (APD) structures fabricated by molecular beam epitaxy is investigated...
Keywords: PARALLEL PROGRAMMING; PROGRAMMING LANGUAGES; MULTIDISCIPLINARY DESIGN OPTIMIZATION; DESIGN ANALYSIS; COMPILERS; CLIMATE MODELS; FLUID FLOW; AIRCRAFT DESIGN; AIRCRAFT MODELS
|Bearing elastohydrodynamic lubrication: A complex calculation made simple - Zaretsky, Erwin V|
The lubricant elastohydrodynamic (EHD) film thickness formula is reduced to a simplified form whereby only the rolling-element bearing inside and outside diameters and speed (in revolutions per minute) and the lubricant type and viscosity (in centipoise) at temperature are required for its use. Additionally, a graph is provided for the first time that is based upon experimental data giving an EHD film reduction factor as a function of contact lubricant flow number...
Keywords: COMPUTER PROGRAMS; RESEARCH FACILITIES; LIBRARIES; PARALLEL PROCESSING (COMPUTERS); PARALLEL PROGRAMMING; SUBROUTINES; USER MANUALS (COMPUTER PROGRAMS); FORTRAN; HEAT TRANSMISSION; PROGRAMMERS
|Message Mode Operations for Spacecraft: A Proposal for Operating Spacecraft During Cruise and Mitigating the Network Loading Crunch - Greenberg, Ed|
The NASA Deep Space Network (DSN) is a world-class spacecraft tracking facility with stations located in Spain, Australia and USA, servicing Deep Space Missions of many space agencies. The current system of scheduling spacecraft during cruise for multiple 8 hour tracking sessions per week currently leads to an overcommitted DSN. Studies indicate that future projected mission demands upon the Network will only make the loading problem worse...
Keywords: CRAY COMPUTERS; OCEANOGRAPHY; PERSONAL COMPUTERS; PARALLEL COMPUTERS; PARALLEL PROGRAMMING; ETHERNET; COMPUTER NETWORKS; LOCAL AREA NETWORKS; CLIMATE MODELS; OCEAN MODELS
|The Research Internet Gateways - Iannucci, David J.|
The Research Internet Gateways (RIG) in experimental local and wide area network testbeds are reported. These RIGs are pre-production Internet routers, capable of forwarding data among multiple networks. Experimental tools for metering data transfers are described. This report documents delivered throughput, performance under traffic load, and failure modes of the units. Behavior of TCP/IP (Transmission Control Protocol/Internet Protocol) file transfers under terrestrial, satellite and multiple ...
Keywords: PARALLEL COMPUTERS; PARALLEL PROCESSING (COMPUTERS); SOFTWARE DEVELOPMENT TOOLS; PROGRAMMING ENVIRONMENTS; PROGRAMMING LANGUAGES; PARALLEL PROGRAMMING; SURVEYS; WORKSTATIONS; SUPERCOMPUTERS
|MIT 6.172 Performance Engineering of Software Systems, Fall 2010|
Instructors: Saman Amarasinghe, Charles Leiserson Lecture videos for 6.172 Performance Engineering of Software Systems, Fall 2010. Also includes one session introducing industry mentors to 6.172. View the complete course: http://ocw.mit.edu/6-172F10 License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
Keywords: performance analysis; algorithmic techniques; high performance; instruction level optimization; cache optimization; memory optimization; parallel programming; scalable distributed systems
|Software Sleuth - NON|
NASA's need to trace mistakes to their source to try and eliminate them in the future has resulted in software known as Root Cause Analysis (RoCA). Fair, Isaac & Co., Inc. has applied RoCA software, originally developed under an SBIR contract with Kennedy, to its predictive software technology. RoCA can generate graphic reports to make analysis of problems easier and more efficient.
Keywords: COMPUTATIONAL FLUID DYNAMICS; COMPUTATIONAL GRIDS; GRID GENERATION (MATHEMATICS); APPLICATIONS PROGRAMS (COMPUTERS); BOEING 777 AIRCRAFT; FLOW DISTRIBUTION; HOLE GEOMETRY (MECHANICS); PARALLEL PROGRAMMING
|Results from computational analysis of a mixed compression supersonic inlet - Saunders, J. D.|
A numerical study was performed to simulate the critical flow through a supersonic inlet. This flow field has many phenomena such as shock waves, strong viscous effects, turbulent boundary layer development, boundary layer separations, and mass flow suction through the walls, (bleed). The computational tools used were two full Navier-Stokes (FNS) codes. The supersonic inlet that was analyzed is the Variable Diameter Centerbody, (VDC), inlet...
Keywords: ALGORITHMS; SORTING ALGORITHMS; COMPUTERIZED SIMULATION; MASSIVELY PARALLEL PROCESSORS; PARALLEL PROCESSING (COMPUTERS); BOUNDARY CONDITIONS; COLLISIONS; PARALLEL PROGRAMMING; RELAXATION METHOD (MATHEMATICS); SHOCK WAVE PROFILES
|Analysis of a Radiation Model of the Shuttle Space Suit - Anderson, Brooke M.|
The extravehicular activity (EVA) required to assemble the International Space Station (ISS) will take approximately 1500 hours with 400 hours of EVA per year in operations and maintenance. With the Space Station at an inclination of 51.6 deg the radiation environment is highly variable with solar activity being of great concern. Thus, it is important to study the dose gradients about the body during an EVA to help determine the cancer risk associated with the different environments the ISS will...
Keywords: COMPUTATIONAL GRIDS; PARALLEL PROGRAMMING; ITERATION; DATA MINING; ARCHITECTURE (COMPUTERS); AUTOMATIC CONTROL; PROGRAMMING (SCHEDULING); COMPUTER SYSTEMS PROGRAMS; MACHINE LEARNING; PROTOCOL (COMPUTERS); DATA PROCESSING EQUIPMENT; APPLICATIONS PROGRAMS (COMPUTERS)
|Infrared Solar Spectroscopic Measurements of Free Tropospheric CO, C2H6, and HCN above Mauna Loa, Hawaii: Seasonal Variations and Evidence for Enhanced Emissions from the Southeast Asian Fires of 1997-1998 - Rinsland, C. P.|
High spectral resolution (0.003/ cm) infrared solar absorption measurements of CO, C2H6, and HCN have been recorded at the Network for the Detection of Stratospheric Change station on Mauna Loa, Hawaii, (19.5 deg N, 155.6 deg W, altitude 3.4 km). The observations were obtained on over 250 days between August 1995 and February 1998. Column measurements are reported for the 3.4 - 16 km altitude region, which corresponds approximately to the free troposphere above the station...
Keywords: GRID GENERATION (MATHEMATICS); DATA STRUCTURES; PARALLEL PROGRAMMING; STRUCTURED GRIDS (MATHEMATICS); CARTESIAN COORDINATES; FORTRAN; MATHEMATICAL MODELS; C (PROGRAMMING LANGUAGE); C (PROGRAMMING LANGUAGE); SUBROUTINES
|Clarifying Objectives and Results of Equivalent System Mass Analyses for Advanced Life Support - Levri, Julie A.|
This paper discusses some of the analytical decisions that an investigator must make during the course of a life support system trade study. Equivalent System Mass (ESM) is often applied to evaluate trade study options in the Advanced Life Support (ALS) Program. ESM can be used to identify which of several options that meet all requirements are most likely to have lowest cost. It can also be used to identify which of the many interacting parts of a life support system have the greatest impact an...
Keywords: PARALLEL PROGRAMMING; FLOW EQUATIONS; GRID GENERATION (MATHEMATICS); PERFORMANCE TESTS; SUPERCOMPUTERS; APPLICATIONS PROGRAMS (COMPUTERS); MATHEMATICAL MODELS; COMPUTER SYSTEMS PROGRAMS; ARCHITECTURE (COMPUTERS); CENTRAL PROCESSING UNITS; MULTIPROCESSING (COMPUTERS)
|Control Design Strategies to Enhance Long-Term Aircraft Structural Integrity - Newman, Brett A|
Over the operational lifetime of both military and civil aircraft, structural components are exposed to hundreds of thousands of low-stress repetitive load cycles and less frequent but higher-stress transient loads originating from maneuvering flight and atmospheric gusts. Micro-material imperfections in the structure, such as cracks and debonded laminates, expand and grow in this environment, reducing the structural integrity and shortening the life of the airframe...
Keywords: CARTESIAN COORDINATES; SOFTWARE DEVELOPMENT TOOLS; EULER EQUATIONS OF MOTION; SOUND WAVES; ALGORITHMS; DIFFERENTIAL EQUATIONS; FLOW DISTRIBUTION; FORTRAN; NOISE GENERATORS; SOUND TRANSMISSION; THREE DIMENSIONAL MODELS; FINITE DIFFERENCE THEORY; PARALLEL PROGRAMMING; SPECTRAL RESOLUTION; RUNGE-KUTTA METHOD; APPLICATIONS PROGRAMS (COMPUTERS); COMPUTER AIDED DESIGN; WAVE PROPAGATION; COMPUTER PROGRAMMING; GRID GENERATION (MATHEMATICS); AEROACOUSTICS; AERODYNAMIC NOISE
|Refurbishment and Automation of Thermal Vacuum Facilities at NASA/GSFC - Dunn, Jamie|
The thermal vacuum facilities located at the Goddard Space Flight Center (GSFC) have supported both manned and unmanned space flight since the 1960s. Of the eleven facilities, currently ten of the systems are scheduled for refurbishment or replacement as part of a five-year implementation. Expected return on investment includes the reduction in test schedules, improvements in safety of facility operations, and reduction in the personnel support required for a test...
Keywords: COMPUTER PROGRAMMING; CONFERENCES; AEROSPACE SYSTEMS; PARALLEL PROGRAMMING; PARALLEL PROCESSING (COMPUTERS); COMPUTERIZED SIMULATION; ARCHITECTURE (COMPUTERS); DISTRIBUTED MEMORY; APPLICATIONS PROGRAMS (COMPUTERS); MULTIDISCIPLINARY DESIGN OPTIMIZATION; PROGRAMMING ENVIRONMENTS; COMPUTER SYSTEMS DESIGN; DISTRIBUTED PROCESSING; COMPUTER SYSTEMS PERFORMANCE; ALGORITHMS; COMPUTER PROGRAMS; PARALLEL COMPUTERS; MULTIDISCIPLINARY RESEARCH; COMPUTER AIDED DESIGN; MATHEMATICAL PROGRAMMING